Molecular Detection of Some Virulence Genes of Salmonella Serotypes Isolated From Poultry in Egypt

Document Type : Original Article

Authors

1 Veterinarian at the Directorate of Veterinary Medicine, Menofiuya province

2 Bacteriology, Mycology and Immunology department, Faculty of Veterinary Medicine, University of Sadat City

3 Microbiology department, faculty of Veterinary Medicine,Zagazig University

Abstract

Salmonellosis is recognized as an important health problem and a major challenge in poultry industry worldwide. This study highlight the prevalence rate of salmonella serotypes in  chickens as well as demonstration of some critical virulence genes by using specific primers sets in PCR reaction. Out of 100 freshly dead chickens, sixteen chicken samples were positive to Salmonella with 16% prevalence rate.The rate of recovery of Salmonellae from the different internal organs showed that the intestine is the most predication seat followed by, heart and liver with (8%), (6%) and (2%), respectively. Salmonella isolates (16) from chickens were serotyping using O and H antigen. The results revealed that S. Enteritidis was the most serotype found in 5 isolates (31.25%) followed by S.Infantis in 4 isolates (25%). Both S.Newlands and S.Kentucky found in 2 isolates 12.5%. Each of S.Ferruch, S.Weybridge and S.Naestved have one isolate (6.25%).The  application of PCR for detection of invA, avrA and stn virulence genes in nine salmonella serovars revealed that these genes (invA, avrA and stn)were detected in 100% of tested strains except S. Naestved does not contain stn gene. Hence, this study recommends that PCR may be used for rapid and sensitive detection of Salmonella and help in understanding the role of these genes in pathogenicity of salmonella infection in poultry.

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